The hierarchy of sources in international law is:
- Custom: it binds all States and includes the general principles of law.
-Treaty: it binds only the contracting States.
- Sources provided by agreements: like the acts of an international organization.
The customary norms are particularly flexible, and thus can be derogated through an agreement. Notwithstanding, a group of norms of general customary international law exist that cannot be derogated, being perceived as mandatory: the cogent norms (i.e. norms of jus cogens). Art 53 of the Vienna Convention on the Law of Treaties (VCLT) of 1969 states that it is void any treaty that, when concluded, is in contrast with an imperative norm of general international law. By “norm of general international law” is meant a norm accepted and recognized by the international community as wholly and automatically binding, that can be derogated only by another similar general international law. According to Art 66 of the VCLT, when a controversy over an agreement contrary to jus cogens occur, the contracting States of the VCLT can unilaterally demand to the International Court of Justice (ICJ) to solve the matter. The VCLT does not expressly suggest which international norms belong to jus cogens, solely affirming that an imperative cogent norm is that that cannot be derogated. Indeed, it is true that a cogent norm is such if the majority of the countries of the international community consider it so and if it includes the typical requirements of custom: the diutirnitas and the opinion juris sive necessitatis. We can uphold that norms of jus cogens include:
a) The fundamental human rights;
b) the principle of national self-determination;
c) the prohibition of the use of force, except for the case of self-defense;
d) the right for development;
e) the respect of the obligations arising from the UN Charter and of the UN binding decisions (cf. Art 103 UN Charter);
f) the decisions taken to contrast international terrorism.
|Allegory of the Russo-Persian|
Treaty of Friendship (1921)
An example of treaty contrary to the principle that forbids the use of force except for self-defense is the Treaty of Guarantee for Cyprus (1960) that authorizes Greece, Great Britain and Turkey (contracting parts of the treaty) to take common or singular actions in cases of modifications in Cyprus’ political status, as regulated by the treaty itself. Another example is the 1921 Treaty of Friendship between the Soviet Union and Iran, which under Art 6 states the Soviet faculty to intervene militarily in Iran if this State would be invaded or the USSR somehow threatened, without prior consent of Iran.
As for the humanitarian interventions, a part of doctrine argues that the prohibition of the use of force has a general cogent nature but it would not concern the so-called humanitarian interventions, by so meaning military measures aimed at saving human lives of endangered citizens either of their own country or of foreign ones.
Examples of treaties in contrast with the principle of self-determination are the Camp David Agreements (1978) and the Peace Treaty between Egypt and Israel (1979), that did not consider nor contemplate the national fates of the Arab inhabitants of the West Bank and the Gaza Strip under Israeli domination.
|The European Court of Human Rights in Strasbourg|
In some cases, according to a part of the doctrine that does not consider the jus cogens as inviolable but rather inderogable and prevailing ordinary customary laws, the international jurisdictions applied old norms on the immunities of States in order to derogate from jus cogens. See for instance the ICJ sentence on an 11th of April 2000 warrant (14/02/2002) in the case Democratic Republic of the Congo vs Belgium, as well as the ICJ sentence on the jurisdictional immunities of foreign States (03/02/2012) in the case Germany vs Italy, and the European Court of Human Rights (ECHR) sentence (21/11/2001) in the case Al-Adsani vs Great Britain.
Furthermore, the binding decisions of the UN Security Council have been considered sometimes superior to the protection of human rights, especially regarding the seizure of assets belonging to alleged terrorists, often contrasting with the jurisprudence of the ECHR.
Finally, the jus cogens seems to have a deterrent effect: this is what the International Criminal Tribunal for the former Yugoslavia (ICTY) stated in the sentence on the case Furundžija (10/12/1998), sustaining that imperative norms (in the present case norms against torture) suggest to States and individuals that the prohibition they compel is inspired by absolute values that nobody can deviate from.
A. Cassese, International Law, USA, Oxford University Press, 2001.